Has anyone tried something like this for polishing stainless steel?

[Jammer]

Have a look at the Milwaukee cordless polishers. There's a big one and a little one and they cost about the same. I have the big one and it's great for what it is. I imagine the little one is too. Fantastic line of tools for working on boats. Batteries last longer than I do.

[MicHughV]

For the life of me, I can't understand this need to polish stainless steel, though I often see a newbie yachtie polishing the stanchions on his new (to him) boat.

Duplex s/s is very difficult to get here in the US. It requires a variety of specialized trades to fabricate, machine, etc

You can buy a product called "Nevr Dull" to polish s/s/ It works quite well, requiring only elbow grease.

https://www.acehardware.com/departme...nts/metal-clea

[MicHughV]

that link didn't work...try this..

/www.amazon.com/Nevr-Dull-NEVER-DULL-POLISH/dp/B00097CRY6/ref=asc_df_B00097CRY6/?tag=hyprod-20&linkCode=df0&hvadid=198113879746&hvpos=&hvnetw= g&hvrand=2915689586152365821&hvpone=&hvptwo=&hvqmt =&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=1015068&hvt argid=pla-511467832232&psc=1

[MicHughV]

I give up.....just google "Nevr Dull"....

[Bellinghamster]

I made my chainplates out of waterjet cut mill finish 316L mill finish plate. I used a 4-1/2 inch angle grinder with flap wheels, sanding discs and 3m scotchbrite finishing pads (the kind that "velcro" onto a spindle adapter/backing pad). I worked up from course to fine, then finished with a buffing pad and metal polishing compound (comes in a slightly waxy block that you apply to the pad when it's spinning. Yeah, had a couple of edge catches but it results in a puff of fuzz, not nearly as scary as a scattering abrasive grinding or cutting wheel, but wear good face protection and always be aware of which direction it's going to want to fly.
Now when I need to do things like that I use the same pads but usually put them on my variable speed polisher. It looks and feels like a 7 or 9 inch angle grinder but has a lot less torque, and speed is adjustable from a couple hundred to a couple thousand RPM. Much tameer than the fixed speed angle grinders. And as a plus, you can use automotive buffing pads on it to polish and wax your gelcoat.

[GILow]

Originally Posted by Bellinghamster

I made my chainplates out of waterjet cut mill finish 316L mill finish plate. I used a 4-1/2 inch angle grinder with flap wheels, sanding discs and 3m scotchbrite finishing pads (the kind that "velcro" onto a spindle adapter/backing pad). I worked up from course to fine, then finished with a buffing pad and metal polishing compound (comes in a slightly waxy block that you apply to the pad when it's spinning. Yeah, had a couple of edge catches but it results in a puff of fuzz, not nearly as scary as a scattering abrasive grinding or cutting wheel, but wear good face protection and always be aware of which direction it's going to want to fly.

Now when I need to do things like that I use the same pads but usually put them on my variable speed polisher. It looks and feels like a 7 or 9 inch angle grinder but has a lot less torque, and speed is adjustable from a couple hundred to a couple thousand RPM. Much tameer than the fixed speed angle grinders. And as a plus, you can use automotive buffing pads on it to polish and wax your gelcoat.

That’s a great sequence of the chainplates.

So, just to clarify, did you do those with an angle grinder and the flap wheels/3m scotch rite pad or did you use the polisher?

Also, what sequence of flap wheel grit ratings did you use?

[fourlyons]

Originally Posted by Bellinghamster

I made my chainplates out of waterjet cut mill finish 316L mill finish plate. I used a 4-1/2 inch angle grinder with flap wheels, sanding discs and 3m scotchbrite finishing pads (the kind that "velcro" onto a spindle adapter/backing pad). I worked up from course to fine, then finished with a buffing pad and metal polishing compound (comes in a slightly waxy block that you apply to the pad when it's spinning. Yeah, had a couple of edge catches but it results in a puff of fuzz, not nearly as scary as a scattering abrasive grinding or cutting wheel, but wear good face protection and always be aware of which direction it's going to want to fly.

Now when I need to do things like that I use the same pads but usually put them on my variable speed polisher. It looks and feels like a 7 or 9 inch angle grinder but has a lot less torque, and speed is adjustable from a couple hundred to a couple thousand RPM. Much tameer than the fixed speed angle grinders. And as a plus, you can use automotive buffing pads on it to polish and wax your gelcoat.

Yep, this is the way I've done it many times, no issue catching an edge with the flap discs. But I finish with a 5" RO sander and fine grits. You can buy kits with all the discs for polishing Corian and stone countertops that work well.

[Fore and Aft]

Gilow the polishing wasn't hard on my Makita electric drill. That tool is almost obsolete in my tool kit now, my cordless drill does 99% of the work I need.
I have a vague recollection of using my random orbital with fine grit paper to work through the first stage of polishing then the Bunnings buff was just the last stage.
MicHughV I have seen a guy with scars on his stomach from using a big electric buff on stanchions. The buff grabbed the lifeline broke it and then whipped the wire across his stomach. Made a bit of a mess judging by the scar.
Cheers

[hpeer]

I have used stuff from these folks. I was able to call them and get good advice. Prices were also very good.

They have a wide selection of finishing products.

https://www.lehighvalleyabrasives.co...ishing&Search=

[Bellinghamster]

GiLow, Yep, I'm pretty sure that was all 4-1/2" angle grinder. Unfortunately I don't remember the progression. (It was 20 years ago... I was rather surprised that I was able to remember, then actually dig up the picture!)
Probably 120 -> 240 grit flap disk to knock down the mill finish, possibly 80 for easing the edges, but it would leave scratches on the flat surfaces that'd be a bugger to get rid of. Then probably sanding pads 240 through 400, or scotchbrite pads (course, medium, fine).

One caution - it's easy to leave swirls or shallow indentations/wobbles that aren't apparent until you approach a mirror finish and end up with a bit of a funhouse look. If I had it to do again, I might try a belt sander for initial mill finish removal (120 -> 240 grit) to keep it flat, then random orbit pad sander 240->360->400->600 then switch to buffing wheel and compound on a variable speed buffer.

It's not rocket science, and I don't believe there is any "best" way. It's time consuming and dirty work no matter how you do it (execept maybe sending it out for electropolishing). You'll learn as you go. Try to not be too aggressive, especially with the coarser grits - deep scratches initially make the rest of the process take exponentially longer! Also, clean and wipe down everything between grits and keep your fine stuff away from the course stuff - a bit of 80 grit abrasive in a final-buffing wheel can send you right back to near the beginning.

[GILow]

Originally Posted by Bellinghamster

GiLow, Yep, I'm pretty sure that was all 4-1/2" angle grinder. Unfortunately I don't remember the progression. (It was 20 years ago... I was rather surprised that I was able to remember, then actually dig up the picture!)

Probably 120 -> 240 grit flap disk to knock down the mill finish, possibly 80 for easing the edges, but it would leave scratches on the flat surfaces that'd be a bugger to get rid of. Then probably sanding pads 240 through 400, or scotchbrite pads (course, medium, fine).



One caution - it's easy to leave swirls or shallow indentations/wobbles that aren't apparent until you approach a mirror finish and end up with a bit of a funhouse look. If I had it to do again, I might try a belt sander for initial mill finish removal (120 -> 240 grit) to keep it flat, then random orbit pad sander 240->360->400->600 then switch to buffing wheel and compound on a variable speed buffer.



It's not rocket science, and I don't believe there is any "best" way. It's time consuming and dirty work no matter how you do it (execept maybe sending it out for electropolishing). You'll learn as you go. Try to not be too aggressive, especially with the coarser grits - deep scratches initially make the rest of the process take exponentially longer! Also, clean and wipe down everything between grits and keep your fine stuff away from the course stuff - a bit of 80 grit abrasive in a final-buffing wheel can send you right back to near the beginning.

Great tips, thank you.

[Coltrek]

That is interesting, I have never used a wool pad like that. My business is SS, and when we have to hand polish, it is usually with a 12" double canvas buffing wheel. The important part is the compound, like Divine Bros, or Shaffner (SPL?). For small stuff, (With your 4" Grinder) you can get a cheap 4" buffing pad at Home Depot or similar, just be careful, as someone mentioned, they can grab! For instance, don't buff into a V shape - buff away from it. Or edges.

[Seaward22]

May want to try bar keepers friend. Used to be on a metal polishing site where a metallurgist recommended this product claiming it passivates the surface. Can confirm the comment about unguarded discs on angle grinders. Had a carbide cutting disc punch a hole in my welding shield (now I don’t let the cashiers touch those discs). Also use it on my Lewmar wenches.

[Mickeyrouse]

I have been using hook-and-loop foam polishing pads on a disc sander for years. Festool, Mirka, and Klingspore - there may be others- all offer pads in grits 500-4000. Obviously you can’t get the inside of a small shackle for instance, but you would be amazed at what you can do.

[Seaward22]

May want to try Bar Keepers Secret. Used to subscribe to a metal polishing site where a metallurgist recommended this product claiming it passivates the surface of stainless steel. Can confirm the comment about disc coming apart on angle grinders had a carbide cutting disc punch a hole through my welding hood. Did make a variable speed box with a dimmer switch for my harbor freight grinder when redoing the blistered hull on my boat. I know this isn’t recommended for electric motors…harbor freight grinder which lasted for many more years of abuse.